Apparatus for handling and mixing blast furnace gaseous materials



J. O. RAICK Jan. 25, 1966 Filed NOV. 25, 1960 K M m W 0 MN M United States Patent O 3,231,254 APPARATUS FOR HANDLING AND MIXING BLAST FURNACE GASEOUS MATERIALS Julien Oscar Raick, 38 Rue Blanche, Brussels, Belgium Filed Nov. 25, 1960, Ser. No. 71,772 Claims priority, application Belgium, Nov. 24, 1959, 464,005, Patent 584,983 5 Claims. (Cl. 266-29) This invention relates to apparatus used in practising the process, described in applicant's United States Patent No. 2,727,816 (hereinafter referred to as the Raick process), utilizing hydrocarbon materials as a source for heat and reducing power in the smelting of iron or other metallic oxides. More particularly this invention relates to a new and improved blast furnace gaseous material handling and mixing means comprising a recess in the internal furnace profile, a burden deflector and fluid-carrying conduits.

The double intervention process of Raick involves introduction of gases at desired temperatures and pressures into the furnace shaft or ascending gas stream at two levels. The lower introduction is at the blast admission level. The higher introduction is at the critical zone level, hereinafter defined. This present invention is directed to a new and improved means for handling, mixing and injecting the materials and gases at the higher or critical zone level.

In accordance with the Raick process oxygen-reformed hydrocarbon material is injected into the ascending gas stream at this higher level. Oxygen-reformed hydrocarbon material is hydrocarbon material which has been reformed by the combined cracking and partial oxidation of the carbon content to produce CO and H with substantially no CO and H 0.

Proper reformation can only be accomplished outside the shaft or rapidly ascending gas stream. Heretofore, reformation of hydrocarbon materials has accomplished not only outside of the shaft or ascending gas stream but also outside the furnace walls in separate auxiliary vessels and conduits. Applicant has discovered that reformation can be more economically accomplished within the furnace walls but still of course outside the ascending gas stream. By the teachings of this invention, reformation takes place within an internal recess in the bosh portion of the furnace wall. Industrially pure oxygen and hydrocarbon materials, preheated as necessary, are introduced through conduits where mixing and reformation occur and from which the oxygen-reformed hydrocarbon material is then injected into the ascending gas stream by the there existing internal pressure differentials. A protrusion of refractory material or the likelihood portion over the recess deflects the descending burden from the mixing and reformation recess. The hydrocarbon gaseous material and oxygen may be mixed before introduction into the recess.

The circumferential recess in the internal wall of the bosh portion of the blast furnace provides a location sheltered from the column or shaft of ascending gases and descending burden. The hydrocarbon material and industrially pure oxygen are discharged through conduits into this recess where reformation and the desired temperature rise takes place immediately. The conventionally constructed blast furnace would normally be adapted for a recess by removal of a volume of the refactory brick sufficiently large to permit continuous mixing and reformation of the material and gas volume required to maintain the continuous balanced operation of the furnace while employing Raicks double intervention process. However, the recess could be constructed by any modification of the furnace as would occur to the man skilled in the art. In addition to performing the 2 function of a mixing and reformation space the recess also allows a loosening and expansion of the descending burden materials which promotes and improves the penetration of the reformed gases into the shaft column.

The burden deflector like the recess extends around the inside of the furnace wall positioned above the recess. The deflector may be made of carbon or any suitable refractory material. The deflector supplements the function of the recess in providing a burden free space where mixing and reformation can be accomplished. The deflector is a desirable but not requisite element of the present invention since at reduced operating capacities a burden free space can be created without a deflector.

Bustle pipes and conduits provide hydrocarbon material and oxygen to the recess. Where mixing is accomplished in the recess, the conduits may be arranged with discharge ends at equal elevation, one over the other or one concentrically disposed in the other. One of these or a similar arrangement, as will suggest itself, will serve to facilitate introductory mixing depending on the particular dimensions of the recess and other furnace characteristics.

A more detailed description is easily understood with reference to the drawings in which FIG. 1 is an elevation sectional view of a blast furnace wall at the bosh and critical zone: FIG. 2 and FIG. 3 show end views of alternative additional conduit pair positions.

FIG. 1 shows portions of the furnace wall refractory brick 8 removed (see dotted profile line 9) and a suitable high temperature refractory material 1 positioned in and extending out from the bosh portion of the brick refractory Wall as modified. This contour of this high temperature refractory creates a recess 2. Two conduits 10 and 11 have equally elevated discharge ends 5, as shown in partial auxiliary view, positioned in the recess 2. Conduit 10 is connected to circumferential bustle pipe 3 which supplies hydrocarbon fuel. Conduit 11 is connected to bustle pipe 4 which supplied industially pure oxygen. Valves 12 and 13 are located in the intake ends of conduits 10 and 11. Blast level tuyere 7 is connected to a ring main or bustle pipe 6. Structural member 14 supports through plate 15 the wall adjacent the stock section of the furnace 16. Cooling vents 1l7 reduce the temperature of the refractory materials 8.

In FIG. 2, an alternative position of the conduits is shown at 10' and 11'. The end elevation view shows discharge ends 5' and 6.

In FIG. 3, another alternative position of the conduits is shown as 10 and 11". The end elevation view shows discharge ends 5" and 6".

The term critical zone refers to that zone of the furnace in which the average temperature of the descending materials lies between about 1150 C. and about 1400 C.

It is to be understood that the invention is not limited to the particular descriptions but is susceptible to changes within the scope of the appended claims.

I claim:

1. In the internal wall of a blast furnace a substantially circumferential recess or suflicient gas handling and mixing volume in the bosh portion of the furnace and at least one pair of conduits with discharge ends positioned in said recess.

2. In a blast furnace, fluid handling and mixing means comprising an internal substantially circumferential recess in the refractory lining of the bosh, said recess having its height approximately equal to its depth, and internal substantially circumferential burden deflector positioned adjacent to and above said recess, said deflector projecting in the furnace shaft a distance not greater than the depth of said recess, at least one pair of conduits a with intake ends connected to circumferential bustle pipes and discharge ends positioned at equal elevation in said recess.

3. In a blast furnace, fluid handling and mixing means comprising an internal substantially circumferential recess in the refractory lining of the bosh, said recess having its height approximately equal to its depth, at least one pair of conduits with intake ends connected to circurriferential bustle pipes and discharge ends positioned at equal elevation in said recess.

4. In a blast furnace of conventional construction including a continuous internal furnace wall formed by the hearth, bosh and stack, means for gaseous material handling and mixing comprising an internal substantially circumferential furnace wall recess of suflicient volume for adequate gas handling and mixing in the bosh portion of the furnace, an internal substantially circumferential burden deflector positioned adjacent to and above said recess and at least one pair of conduits with discharge ends positioned in said recess.

5. A blast furnace in accordance with claim 4 having an internal refractory lining in which the furnace Wall recess is formed in said refractory lining and in which the burden deflector is positioned on said refractory lining.

References Cited by the Examiner UNITED sTATEs PATENTS 502,482 8/1893 Dauber 75-41 972,126 10/ 1910 Munson 266-30 1,448,340 3/1923 Fleischer 266-25 1,850,009 3/1932 Gronwall et al. 266-25 2,010,073 8/1935 Frank} 266-25 2,790,711 4/1953 Sellers et a1. 75-41 2,833,643 5/1958 Newman 266-29 2,859,106 11/1958 Antonsen 75-49 FOREIGN PATENTS 586,015 12/1924 France.

WHITMORE A. WILTZ, Primary Examiner.

Examiners. 

1. IN THE INTERNAL WALL OF A BLAST FURNACE A SUBSTANTIALLY CIRCUMFERENTIAL RECESS OR SUFFICIENT GAS HANDLING AND MIXING VOLUME IN THE BOSH PORTION OF THE FURNACE AND AT LEAST ONE PAIR OF CONDUITS WITH DISCHARGE ENDS POSITIONED IN SAID RECESS. 